Races
Grindstone
The Grindstone 100K hits Reddish Knob and the same Appalachian ridges on a tighter cutoff.
100 km+8,211 ft-8,211 ft18 hours1,342 ft to 4,259 fttech 6/106 stationsAppalachian ridgesUTMB IndexWSER qualifierSeptember
Distance100 km
Gain+8,211 ft
Loss-8,211 ft
Altitude1,342 ft to 4,259 ft
Technicality6/10
Air45°F to 85°F
- Start1,342 ft
- High4,259 ft
- Low1,342 ft
- Finish1,342 ft
- Natural Chimneys Park at mile 0.0
- Grindstone mile 12 at mile 12, cutoff 3.6 hours
- Grindstone mile 25 at mile 25, cutoff 7.2 hours
- Grindstone mile 37 at mile 37, cutoff 10.799999999999999 hours
- Grindstone mile 50 at mile 50, cutoff 14.4 hours
- Finish Virginia at mile 62, cutoff 18 hours
Geometrycourse math
Steepest drop1,224 ft-10.6% over 2.2 mi
Night miles21 misunset near 18:00 local
The cruxReddish Knob on an eighteen-hour clock (near mile 40)
Course DNA
The Course
Grindstone runs 100 km through Natural Chimneys Park, Virginia. +8,211 ft gain and -8,211 ft loss. Surfaces skew 85% trail / 10% jeep / 5% paved. Reddish Knob on an eighteen-hour clock. High point near 4,259 ft. Low near 1,342 ft. September temps run 45°F to 85°F. The course rewards patience early and punishes rushed descents after mile 31.
The Work
Train for 8,211 feet of climbing across 100 km. Back-to-back long runs on trail. Practice power-hiking grades above 15 percent. 18 hours total means limited margin: rehearse fueling every 45 to 60 minutes and downhill eccentric work weekly. Technicality 6/10. Build a block that simulates the crux near mile 40.
Kit
September in Natural Chimneys Park, Virginia: plan for 45°F to 85°F. Mandatory shell if rain is in forecast. Headlamp with spare batteries if 18 hours pushes past dark. Poles help on sustained climbs above mile 16. Vest capacity for 2 liters minimum. Shoes matched to 85% trail: lugs for mud, rock plate if the course turns technical after mile 31.
Race Day
Hold effort through mile 16. The field often splits on the first big climb after mile 31. Reddish Knob on an eighteen-hour clock near mile 40 is where time is won or lost. Walk the steep pinches. Run the flats and gentle downhills. Crew at major aids: socks, calories, ice if hot. Transitions under 5 minutes when possible. Final third is 21 miles of fatigue management. Finish with reserve for the last descent.
Results
Grindstone finish lines.
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